In a case where a thermoplastic resin composition is employed for various applications such as a housing of (i) a personal computer and (ii) a display, an electronic device material, and automotive exterior and interior, since plastic has a less thermal conductivity than an inorganic substance such as a metal material, there may be a problem that it is difficult to release generated heat. In order to solve such a problem, an attempt has been widely made to obtain a highly thermally conductive resin composition by blending a large amount of highly thermally conductive inorganic substance in a thermoplastic resin. As the highly thermally conductive inorganic compound, it is necessary to blend, in a resin, a highly thermally conductive inorganic substance such as graphite, carbon fiber, alumina, or boron nitride generally in an amount of not less than 30 vol % and further in an amount of as much as not less than 50 vol %. However, even in a case where a large amount of inorganic substance is blended in the resin, since the resin itself has a low thermal conductivity, there has been a limit to the thermal conductivity of the resin composition. For this reason, there is a demand for increasing the thermal conductivity of the resin itself.
For example, an epoxy resin described in Patent Literature 1 and a bismaleimide resin described in Patent Literature 2 are reported as a thermosetting resin in which a resin itself has an excellent thermal conductivity. These resins, which have a certain level of thermal conductivity, have a complex molecular structure, so as to be difficult to be produced. The epoxy resin described in Patent Literature 3 is relatively simple to be synthesized. However, the epoxy resin has an insufficient thermal conductivity.
Meanwhile, few research reports are provided on a thermoplastic resin in which a resin itself which is injection molded without a special molding process such as extension and magnetic field orientation has a high thermal conductivity. Patent Literature 4 is one of such few research reports. As to a thermoplastic resin described in Patent Literature 4, it is possible to obtain, by carrying out an injection molding, a molded member having a high thermal conductivity. However, a melt fluidity of the molded member is insufficient in a case where an inorganic filler is blended. For this reason, there is a demand for a higher melt fluidity in view of molding processability.